Crotalidae Immune F(ab')2 (Equine)

• Crotalidae Immune F(ab')2 (Equine)
• Anavip
• Antivenin
• Antivenin (Crotalidae) Immune F(ab’)2 (Equine)
• Antivenom
• Antivenom (Crotalidae) Immune F(ab’)2 (Equine)
• Crotalidae Immune F(ab')2 (Equine)
• Crotalidae Immune Fab2 (Equine)
• Crotaline Antivenin Immune F(ab’)2 (Equine)
• Crotaline Antivenom Immune F(ab’)2 (Equine)
• Snake Antivenin F(ab’)2 (Equine)
• Snake Antivenom F(ab’)2 (Equine)

There are no dosage adjustments provided in the manufacturer’s labeling.

Reconstitute the contents of each vial with 10 mL of sterile normal saline; gently swirl to mix. The solution should be clear to yellow/green and opalescent. Do not use if otherwise discolored or turbid. Dilute dose (eg, 10 vials) to a total volume of 250 mL with sterile normal saline. Fluid volumes may need to be adjusted for very small children or infants.

IV: Infuse intravenously over 60 minutes. Infuse at a rate of 25 to 50 mL/hour for the first 10 minutes, carefully monitoring for any allergic reactions. If no reactions occur, increase the infusion rate to 250 mL/hour until completion. Discontinue the infusion if any allergic reaction occurs and institute appropriate emergency treatment. Reassess the risk to benefit ratio before continuing the infusion.

Concerns related to adverse effects:

• Acute hypersensitivity reactions: Derived from equine (horse) immune globulin F(ab’)2 fragments; anaphylaxis and anaphylactoid reactions are possible, especially in patients with known allergies to horse protein. Patients who have had previous treatment with Crotalidae immune F(ab’)2 or other equine-derived antivenom/antitoxin may be at a higher risk for hypersensitivity reactions. In patients who develop an anaphylactic reaction, discontinue the infusion and administer emergency care. Immediate treatment (eg, epinephrine 1 mg/mL, corticosteroids, diphenhydramine) should be available.

• Delayed serum sickness: Delayed serum sickness may occur, usually within 2 weeks; monitor patients with follow-up visits for signs and symptoms (eg, arthralgia, fever, myalgia, pruritus, rash, urticaria).

Dosage form related issues:

• Cresol: Product may contain small amounts of cresol resulting from the manufacturing process; local reactions and generalized myalgias may occur.

• Disease transmission: Product derived from equine (horse) plasma; may potentially contain infectious agents (eg, viruses) which could transmit disease.

Animal reproduction studies have not been conducted. In general, the health and prognosis of the mother should be taken into consideration when using medications as antidotes; they should be administered to pregnant women if there is a clear indication for use and should not be withheld because of fears of teratogenicity (Bailey 2003). Experience with the use of antivenom in pregnancy is limited; however, treatment with antivenom should be considered in snake envenomations in which it is usually required as definitive management or in envenomations refractory to supportive care (Brown 2013).